Stroke prevention in atrial fibrillation: Beyond anti-clotting drugs

More than five million Americans have atrial fibrillation, a heart rhythm disorder commonly known as afib. During a bout of afib, the heart’s upper chambers (atria) suddenly start to quiver ineffectually. When that happens, blood tends to pool — and possibly form clots — in a small pouch that protrudes from the top of the left atrium. This ear-shaped sac is called the left atrial appendage (LAA).

About 90% of blood clots in the heart form in the LAA. These clots can escape the heart and travel to the brain, blocking blood flow and causing an ischemic stroke. Most people with afib take anti-clotting medications that help prevent these strokes. However, some people develop serious bleeding problems while taking those medications. Also known as blood thinners, these drugs are especially risky for older people who are vulnerable to head injuries from falls, increasing the risk of bleeding in and around the brain.

“Both of these groups of people are possible candidates for procedures that close off the left atrial appendage,” says Dr. Thomas Tadros, a cardiologist at Harvard-affiliated Brigham and Women’s Hospital. Anyone with afib who’s had a stroke despite being on an anti-clotting drug might also benefit, he adds. The usual procedure involves delivering a device that blocks the opening of the LAA.

A device that traps clots

Find stability with a charitable gift annuity

When you establish a charitable gift annuity to benefit HMS, your gift will provide you and/or a loved one with a fixed income for life while supporting our mission to improve health and well-being for all.

One device, the Watchman, was approved by the FDA in 2015. As with many heart devices, it’s deployed through a catheter that a cardiologist snakes through a leg vein up to the heart. The tiny, basket-like device is then placed over the opening of the LAA (see illustration).

“People need to keep taking anti-clotting drugs for about six weeks until a layer of cells grows over the device. But after that, they can stop those drugs,” says Dr. Tadros. Early studies showed the Watchman prevented strokes in people with afib about as well as warfarin (Coumadin). At the time, warfarin was still widely used to prevent clotting but has now been largely replaced by newer drugs known as DOACs (see “Anti-clotting drugs”).

More recent trials compared DOACs to the closure devices, including the Watchman and a similar device called the Amulet, which was FDA-approved in August 2021. The rates of strokes, bleeding, and cardiovascular death were similar regardless of approach. Larger studies are currently under way.

Other research using data from Medicare suggests that for patients, the Watchman is less expensive than the average cost of anti-clotting medications and the drugs’ bleeding-related complications within five years. Newer iterations of the device are more flexible and come in a wider range of sizes, making them easier to position, says Dr. Tadros.

People who get an LAA closure device usually receive general anesthesia and stay overnight in the hospital. But they rarely need any pain medications and can return to doing most regular activities right away, with the exception of running or doing heavy lifting in the first few weeks, Dr. Tadros says.

Anti-clotting drugsSome people with afib take warfarin (Coumadin) to prevent blood clots, but most take one of these direct oral anticoagulants, known as DOACs:apixaban (Eliquis)dabigatran (Pradaxa)edoxaban (Savaysa)rivaroxaban (Xarelto).

Surgical options

Some people with afib need open heart surgery to address another problem, such as narrowed coronary arteries or a failing heart valve. For them, removing or closing the LAA during the surgery can reduce their risk of a stroke by about 30%, according to a large international study published in The New England Journal of Medicine earlier this year. However, people in the study were supposed to continue taking anti-clotting medications after surgery; the stroke-prevention benefit is intended to add to the protective effect of the drugs, not to replace it.

The take-home message

About one in seven strokes are caused by afib, and these strokes tend to be more severe than strokes with other underlying causes. People with afib who are doing well on warfarin or a DOAC should feel confident that these drugs — when taken consistently — cut their stroke risk by about two-thirds. But those who’ve already had a stroke while on anticoagulants, have bleeding problems, or are prone to falls may want to discuss LAA closure options with their cardiologist.

Bible verses for today’s meditation and inspiration: Matthew E. McLaren

Rejoice always, pray continually, give thanks in all circumstances; for this is God’s will for you in Christ Jesus. 1 Thessalonians 5:16-18 NIV

The Lord your God is with you, the Mighty Warrior who saves. He will take great delight in you; in his love he will no longer rebuke you, but will rejoice over you with singing. Zephaniah 3:17

Rejoice in the Lord always. I will say it again: Rejoice! Philippians 4:4 NIV

Be joyful in hope, patient in affliction, faithful in prayer. Romans 12:12 NIV

When anxiety was great within me, your consolation brought me joy. Psalm 94:19 NIV

The Lord has done it this very day; let us rejoice today and be glad. Psalm 118:24 NIV

Though the fig tree does not bud and there are no grapes on the vines, though the olive crop fails and the fields produce no food, though there are no sheep in the pen and no cattle in the stalls, yet I will rejoice in the Lord, I will be joyful in God my Savior. Habakkuk 3:17-18 NIV

You make known to me the path of life; you will fill me with joy in your presence, with eternal pleasures at your right hand. Psalm 16:11 NIV

Though you have not seen him, you love him; and even though you do not see him now, you believe in him and are filled with an inexpressible and glorious joy, for you are receiving the end result of your faith, the salvation of your souls. 1 Peter 1:8-9 NIV

Recommended contacts for prayer request and Bible study

It Is Written

Be the first to comment

Leave a Reply

Show Buttons
Hide Buttons